JPS624051A - Vessel with easy-open type cover - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a container whose opening is sealed with a lid formed of a metal foil sheet, and which has a gripping portion at one end on the upper surface of the lid. An easy-to-open type in which a band-shaped pull-opening piece is fixed more firmly than the tear strength of the lid, and the lid is broken by pulling up the grip of the pull-opening piece against the lid, and the lid is opened in a predetermined shape. Concerning containers with lids.

(Prior Art) Conventionally, in a container in which a lid formed of a metal foil sheet is fixed to the opening of the container body, a method has been proposed in which a pull-opening piece is fixed to the lid and the lid is split open by pulling the opening piece. Concerning the container, for example, it is disclosed in Japanese Utility Model Application No. 54-97342, etc., but this structure has the disadvantage that it cannot be opened neatly into a predetermined opening shape because it is opened along the shape of the tension opening piece itself. there were.

In order for the lid opening to be neatly split into a predetermined shape by the tension opening piece and to provide a practical container, it is necessary to satisfy the following three points.

(1) Separately from the tension opening piece, an opening edge that regulates the cleavage position is predetermined, and when the tension opening piece is pulled, the metal foil sheet initially cleaves cleanly, and furthermore, the cleavage is directed toward the predetermined opening edge. Moreover, the cleavage must be performed neatly along the opening edge.

(2) The tensile aperture piece must be firmly adhered to the metal foil sheet, and the adhesive strength must be maintained at a level equal to or higher than the tear strength of the metal foil sheet even after aging.

(3) The tensile opening piece itself has sufficient tensile strength to prevent it from breaking when the metal foil sheet is split open, and maintains its strength even after time, and will not tear due to the tensile force at the time between tears. No.

The present inventors have proposed a container having a structure in which a metal foil sheet lid is fixed to the opening of the container body together with a ring-shaped member, and a tension opening piece is adhered to the lid via an adhesive layer, and the tension opening piece is pulled. Therefore, we conducted a study to obtain a container that can be neatly split open into a predetermined shape defined by a ring-shaped member.

As a result, regarding item (1) above, the shape of the tension opening piece has a grip portion at one end, a guide edge toward the opening edge of the ring-shaped member, and a narrow strip shape along at least half the circumference of the opening edge. It was proposed in Japanese Utility Model Application Laid-Open No. 57-177932, etc. that by doing so, the opening can be cleaved into a predetermined shape specified by the opening edge.

In addition, there is an improvement in which a notch or the like is inserted near the gripping part of the tension opening piece to form a weakly rigid part to improve the initial opening property, and an improvement in which the shape of the tension opening piece is made into a spiral shape to improve the cleavage opening property of a predetermined shape. Moji Kai 58-185
It was proposed in No. 526, Utility Model Application Publication No. 59-32666, etc.

An example of the configuration is shown in FIGS. 8 and 9. That is, the lid a shown in FIGS. 8 and 9 is made of a composite sheet or a single layer sheet made by laminating a thermoplastic synthetic resin onto a metal foil sheet such as aluminum foil, and covers the opening of the container body C with this sheet and covers the opening of the container body C with a metal foil sheet or a single layer sheet. A ring-shaped member made of plastic is wrapped or fused to the opening edge of the container body C. On the upper surface of the lid a within the opening edge d of the ring-shaped member is a band-shaped piece made of thermoplastic synthetic resin, etc., which is formed in an annular shape and has a gripping part e at one end. It is strongly fused or bonded.

When opening the lid a, when the gripping part e is pulled up against the ia with a fingertip, the starting end Q of the fixed part between the pulling opening piece f and the lid a is pulled up.
Initial cleavage occurs at

Next, after this initial tearing, when the grip part e is pulled up, the tear along the outer guide edge provided on the pull opening piece f reaches the opening edge d of the ring-shaped member S, and the point X is detected. A tear occurs along the inner edge i of the tension aperture piece f as a starting point. When the grip part e is pulled up again, the tear that has reached the opening edge d progresses along this opening edge dk:, and the tear along the inner edge i progresses to approximately half the circumference, and as a result, lla
If there is slack in the center of the lid, depending on the direction of tearing, the lid a
The tearing at the inner edge i is interrupted because it becomes easy to sag.

Therefore, the tearing stress is concentrated only along the opening edge d, and only the tearing along the opening edge d is sustained until the end, resulting in a complete opening.

Such containers are generally stored for long periods of time under relatively high temperature conditions in the summer, and even after long periods of storage under such temperature conditions, the metal foil sheet is removed by the tension opening piece. When trying to break and tear the metal foil sheet, the tensile opening piece must not peel off from the metal foil sheet before the metal foil sheet is torn, so it is necessary to maintain adhesive strength for a long period of time under the above usage conditions. be.

In the past, various studies have been conducted on adhesives used for adhering to metal materials such as metal foil sheets, and it is known that polyolefins, olefin copolymers, derivatives of these, or those using crosslinking agents added thereto are used. However, the former has extremely low adhesion to metal materials (it is not practical), and the latter requires crosslinking treatment after being applied to the metal material, so it cannot be used for applications such as the present invention.

On the other hand, adhesives using olefin-α,β-unsaturated carboxylic acid copolymer resins and ionomer resins having carboxyl groups in their side chains can be heat-fused to metal materials.
It has excellent moldability, is strong, has moderate elasticity, has good abrasion resistance, and has excellent cold resistance, and complies with US FDA standards and Japan's Ministry of Health and Welfare Notification No. 20 (February 16, 1981). It is suitable as an adhesive for food packaging containers as it has passed the standards.

However, according to the studies of the present inventors, an easy-to-open container lid in which a tension opening piece f is fused to a metal foil sheet as shown in FIGS. 8 and 9 using an adhesive using such a synthetic resin material has been found. After the container is manufactured, the tensile opening piece f is glued to the metal foil sheet with sufficient adhesive strength for a short period of time, and there is no problem with initial opening and subsequent tearing, but in summer When stored in a high-temperature environment such as °, the initial cleavage occurs at the opening, and the tension opening piece f attempts to tear the metal foil sheet along the opening edge d of the ring-shaped member. When f is pulled up, the tension opening piece f peels off along the inner edge i of the tension opening piece f, and the tear along the inner edge i invades under the tension opening piece f before progressing to the semicircumference. Tearing is interrupted.

As a result, the bending of the lid a is insufficient, and the tearing stress along the opening edge d is dispersed, causing the tearing to occur at the intermediate portion between the opening edge d and the tension opening piece f, as shown in Fig. 8. In addition, uncut portions of the ia were sometimes produced at the opening edge d around 180 degrees from the initial opening.

When stored for an even longer period of time, the tensile opening piece f sometimes peeled off from the lla when it was torn.

As a result of investigating the cause of this problem, the inventor of the present invention found that the main cause was a decrease in adhesive strength due to deterioration over time of the adhesive bonding the tension opening piece r to 13a.

Basically, the main cause of this decrease in adhesive strength over time is that atmospheric oxygen diffuses into the adhesive during storage, and the main chain of the copolymer resin undergoes oxidative deterioration. I fixed it.

That is, when it is necessary to firmly bond the metal foil sheet and the tension aperture piece f, the adhesive is heated to a high temperature of 160° C. to 230° C., which far exceeds the melting point (70° C. to 120° C.), for several seconds.
It is necessary to heat the adhesive for several tens of seconds to fuse it, which causes the adhesive to oxidize beyond the induction period, or when stored after fusion, the induction period for oxidative deterioration is significantly shortened. Although it shows strong adhesive force immediately after fusion, deterioration gradually progresses even at room temperature, causing a decrease in adhesive force. This decrease in adhesive strength is particularly noticeable at temperatures above 50 DEG C., and when used as an adhesive for the tensile opening piece f, the same angle occurs in practical use after only 2 to 3 weeks.

In particular, the tensile aperture piece f has a relatively narrow band shape from the viewpoint of good cleavage opening property.

Since the shape follows the opening edge of the pull-shaped member f, oxygen diffuses into the adhesive layer from both sides thereof, causing adhesive deterioration in the adhesive layer under the inner and outer edges of the tension opening piece f.

On the other hand, considering the affinity between the tension opening piece f and the adhesive layer,
It is preferable that the tension opening piece f be formed of the same synthetic resin as the adhesive layer, but due to the above-mentioned deterioration of this resin over time, the tension opening piece f itself may be torn off when the metal foil sheet is opened. There is a risk of Therefore, when the tension opening piece f is formed of the same synthetic resin as the adhesive layer, it is necessary to take measures to prevent this deterioration over time.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned inconveniences, and makes it possible to easily and reliably tear open a lid made of a metal foil sheet using the tension opening piece, and to make it possible to easily and reliably tear open a lid made of a metal foil sheet. It is an object of the present invention to provide an easy-to-open container with a lid, which allows the lid to be easily and reliably torn open over the entire surface following the initial tearing.

Another object of the present invention is to provide a means for opening a container by pulling up the tension opening piece, even if the tension opening piece adhered to the lid made of a metal foil sheet is stored under high temperature conditions for a long period of time. To provide an easy-to-open container with a lid that can be reliably opened along the edge of a ring opening without causing any nicks or the like during the opening operation.

Furthermore, another object of the present invention is to provide an easy-to-open type in which the above-mentioned tensile opening piece is adhered to a lid made of a metal foil sheet with an adhesive layer that does not reduce adhesive strength even when stored under high temperature conditions for a long period of time. The purpose of the present invention is to provide a container with a lid.

Still another object of the present invention is to form the tensile opening piece with a resin composition whose tensile strength does not decrease even when stored under high temperature conditions for a long period of time, and to attach the tensile opening piece to a metal foil through an adhesive layer. It is an object of the present invention to provide an easy-to-open container with a lid that is adhered to a lid made of a sheet and suppresses a decrease in the adhesive strength of the adhesive layer over time.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a first invention in which a lid made of a metal foil sheet is fixed to the opening of the container body together with a ring-shaped member, and the upper surface of the lid a gripping portion at one end and an outer guide edge facing the opening edge of the ring-shaped member;
An easy-to-open lidded container in which a band-shaped tensile opening piece along at least half the circumference of the opening edge of a ring-shaped member is fixed to the lid through an adhesive layer, the adhesive layer being olefin-α, Zero phenolic antioxidants for β-unsaturated carboxylic acid copolymer resins or ionomer resins
, 01~o, sa m% gold-containing resin composition. In a second aspect of the invention, a lid made of a metal foil sheet is fixedly attached to the opening of the container body together with a ring-shaped member, and the upper surface of the lid has a gripping portion at one end, and a gripping portion is provided at one end toward the opening edge of the ring-shaped member. In an easy-to-open container with a lid, in which a band-shaped tensile opening piece having an outer guide edge and extending along at least half the circumference of the opening edge of a ring-shaped member is fixed to the container through an adhesive layer more firmly than the tear strength of the lid, the adhesive The agent layer and the tensile aperture piece are made of an olefin-α,β unsaturated carboxylic acid copolymer resin or an ionomer resin, and the tensile aperture piece contains 0.01 to 0 phenolic antioxidant to the resin.
．． 5111%, and the adhesive layer of the tension opening piece is fused.

Next, the present invention will be explained in more detail with reference to FIGS. 1 to 5 showing an example of implementation of the present invention.

Fig. 1 is a plan view of the embodiment, and Fig. 2 is a plan view of the embodiment.
(1) In the cross-sectional view along the line, (1) is a lid that is wrapped around the upper opening of the can body (2) together with a ring-shaped member (3). More specifically, the lid (1) is made by laminating an adhesive layer (5) made of a synthetic resin composition to be described later on the top surface of an aluminum foil (4), and is made of metal such as tin plate, tin-free steel, or thermoplastic synthetic resin. The opening of a ring-shaped member (3), which is made of resin and has a similar shape to the flange of a normal can lid, is covered and bonded to the back surface of the member (3) with the adhesive layer (5). And the lid (1) is a ring-shaped member (3)
The lid (1) may be made of a single layer or multiple layers of aluminum foil if necessary.Also, the adhesion between the lid (1) and the can body (2) is as follows. , the lid (1) is fixed so as to directly cover the opening of the can M (1), and then the ring-shaped member (3) is superposed on the W (1) to form the can body (1).
) may be attached to the opening of the

(7) is a narrow band-like piece, the terminal end (9) extends in an annular shape toward the starting end (8), and the starting end (9) extends in an annular shape.
8) and a terminal end (9) are separably connected, and has a ring-shaped gripping part (IO) connected to the starting end (8). ) is attached to the top surface of the lid (1) by the adhesive layer (5) at an appropriate distance from the opening edge (6) of the ring-shaped member (3).
) is fused and provided with a stronger tear strength than that of The position of the tension opening piece (0 and M(1)) is shown in Figure 1 with the position of the breaking water as the starting end di of the fixed part, and the other parts are fixed to the lid (1). .The grip part QG is the lid (1)
It suffices if it is separated from the upper surface of the board or adhered to such an extent that it can be easily peeled off.

Furthermore, the material of the tension opening piece (7) must be higher than the tear strength and tensile strength of the lid (1), and its adhesion to the lid (1) must also be higher than the tear strength of the lid 4). It must be fixed by the adhesive layer (5).

O3 is attached to the lower side of the grip part 00 facing the starting end (11) of the adhesive part with the lid (1) of the tension opening piece (n).
It is a thin part formed by crossing the grip part (10), and is made to be easily bent at the thin part O when the grip part (10 is pulled up in the direction away from the lid (1). 3. As shown in the figure, pull the top surface of the grip part (1G) and open the opening piece (7).
), while creating a gap between the grip part ao and the upper and lower lids (1).
It may be formed as follows.

(2) is a weak rigid structure in which a concave portion is formed on the upper surface of the tension opening piece (7) that is slightly inserted into the tension opening piece (7') side from the starting end a1 of the fixed part between the tension opening piece (7) and the lid (1). A notch-shaped concave portion was formed in the opening to provide a rigid portion having a lower rigidity than that of the tension opening piece (7). A tension opening piece (7) and a lid (1) are placed between the weakly rigid part a3 and the starting end at+ of the fixed part.
11 by the tension opening piece (7).
This becomes the initial cleavage part when tearing (1).

(1/D is a guide edge facing the opening edge (6) of the ring-shaped member (3) formed on the outside of the starting end (8) facing the terminal end (9) of the tension opening piece (7). so that when the lid (1) is torn open by the tension opening piece (7), the tearing of the lid (1) along the outer edge 0 of the tension opening piece (7) is directed toward the opening edge (6). Function.

0e is the starting end (8) and the ending end (9) of the tension opening piece (7)
This is a connection piece that connects the two in a separable manner.

Then a layer of adhesive (
To explain 5) in detail, in the present invention, as the adhesive layer (5), a phenolic antioxidant is added from 0.01 to 0.5 to an olefin-α,β unsaturated carboxylic acid conjugate resin or an ionomer resin. A resin composition containing % by weight is used.

First, the olefin-α, β-unsaturated carbo-281 resin used in the present invention contains α-olefins such as ethylene, propylene, and butene, and α, β-unsaturated carboxylic acids such as acrylic acid and methacrylic acid as essential components. Examples include copolymer resins used as

In the present invention, a copolymer resin containing ethylene and methacrylic acid as essential components is particularly preferred since it has excellent initial adhesion and toughness.

Examples of such copolymer resins include Nucleol 410.
, 403, 925, 010. 035 (the above is a trade name of DuPont Mitsui Polychemicals Co., Ltd.), etc. can be used.

In addition, as the ionomer resin used in the present invention, a part of the side chain carboxyl group of a copolymer resin having a carboxyl group in the side chain using an α-olefin and an α,β unsaturated carboxylic acid as essential components as described above. Examples include resins neutralized with metals such as sodium, potassium, zinc, magnesium, and calcium.

In the present invention, an ionomer resin in which a part of the side chain carboxyl groups of an ethylene-methacrylic acid copolymer resin using ethylene and methacrylic acid as essential components is neutralized with zinc or sodium has excellent initial adhesion and toughness. preferable.

Such ionomer resins include, for example, Surlyn 15.
55, 1560, 1601, 1605, 170
7, A-1650, A-1652, A-Low 8102, A-1706 (all DuPont product names), Himilan 155
5, 1601, 1605, 1650, 1652
, 1702, 1705, 1855 (all trade names of DuPont Mitsui Polychemicals), etc. can be used.

Further, in the present invention, polyolefins such as polyethylene and polypropylene, and olefin-based polymers containing no carboxyl group such as ethylene vinyl acetate copolymer may be mixed with the resin.

The density of the carboxyl group of the copolymer resin or ionomer resin having a carboxyl group is 0.4X10-3~
3.6X10-3 equivalents/gram, preferably 0.5X1
0″3~2.9X10-′ equivalent/gram is suitable;
If it is less than 0.4 x 10' equivalent m/g, the initial adhesive strength to the metal material will be low, and if it is more than 3,6 x 1 G-3 equivalent/g, the film formability and moisture resistance of the resin will decrease.
Adhesion to metal materials and protective effect on metal materials are reduced.

In addition, the ionomer resin preferably has a structure in which 70% or less of the side chain carboxyl groups contained within the above range is neutralized with zinc or sodium, etc. If it exceeds 70%, heat resistance and film formability decrease. do.

In addition, the antioxidant used in the present invention has good compatibility with the resin of the present invention, is effective in a small amount, and does not color the surface of the metal material, elute or volatilize into the contents of the container, or cause flavoring. Suitable materials are those that do not have a negative effect on the

Phenolic antioxidants are suitable for the present invention as they meet these requirements, and are particularly suitable for food packaging containers because they rarely color the resin and have extremely low toxicity.

CIBA-Geigy (CIBA-
GEIGY) Noilganox (IRQANOX)
Additives, such as 1,6-hexanethiol bis[3-
(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (Irganox 259), 1.
3.5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-humanOxybenzyl)benzene (Irganox 1330), 2.4-bis-(n-octylthio)-6-(4 -Hydroxy-3゜5-di-t-butylanilino)-1,3,5-triazine (Irganox 565), 2,2-diodiethylenebis[3-(3
,5-di-t-butyl-4-hydroxyphenyl)propionate] (Irganox 1035), 2゜2-
Thiobis(4-methyl-6-t-butylphenol) (
Irganox 1081), N.

N'-hexamethylenebis(3,5-di-butyl-4-hydroxy-hydrocinnamamide) (Irganox 1098), 3,5-di-t-butyl-4-hydroxybenzylphosphonate Diethyl ester (Irganox 1222), 1,1,3-tris-(5
-t-butyl-4-hydroxy-2-methylphenyl)
-butane, 1.3.5-tris-(3;5-di-t-butyl-4-hydroxybenzyl)-isocyanute, etc., and further, antioxidants approved by the US FDA,
For example, pentaerythrityl-tetrakis [3-(3,5
-di-t-butyl 4-hydroxyphenyl)propionate] (Irganox 1010), triethylene glycol-bis[3-(3-t-butyl-5-methyl-
4-hydroxyphenyl)propionate (Irganox 245), octadecyl-5-(3,5-di-t
-butyl-4-hydroxyphenyl)propionate (Irganox 1076), 2-t-butyl-α-(
3-t-butyl-4-hydroxyphenyl)-P-cumenylbis(P-nonylphenyl)-phosphite,
2-(3'-t-butyl-2-hydroxy-5'-methylphenyl)-5'-chlorobenzotriazole, 4
゜4'-Butylidene bis(6-t-butyl-m-cresol), 4.4''-cyclohexylidene bis(2-cyclohexylphenol), 4゜4'-methylene bis(
2,6-di-t-butyl-phenol), 2,2-methylene bis(4-methyl-6-t-butylphenol),
2゜2'-Methylbis[6-(t-methylcyclohexyl)]-]P-cresol4.4--Thiobis(6-t
-butyl-m-cresol), tris(2-methyl-4
-Hydroxy-3-t-butylphenyl)butane, 4-
Hydroxymethyl-2,6-di-t-butylphenol and the like can be used.

In the present invention, the antioxidant is used in an amount of 0.01 to 0.5% by weight, preferably 0.05% by weight, based on the resin.
~0.3 fold f! i % Ka'14 L Thio'Q, 0.
If the amount is less than 0.01% by weight, the excellent initial adhesive strength cannot be maintained for a long period of time, and the adhesive strength decreases over time, especially at high temperatures. Moreover, if it exceeds 0.5% by weight, the antioxidant will precipitate on the interface or surface when the resin is formed into a film and fused to the lid of the metal foil sheet, which is not preferable.

In the present invention, the above-mentioned resin composition is used as an adhesive layer to bond the tension aperture piece to the lid of the metal foil sheet, but such a structure does not adhere to the lid of the metal foil sheet even if stored under high temperature conditions for a long period of time. It is clear from the above description that the adhesive strength between the material and the tensile aperture piece does not deteriorate over time and is useful.

To explain the opening operation of the above embodiment, first, as shown in the fourth diagram, when the grip part αG is held between the fingertips and pulled up, the grip part (IG) is bent at the thin part 0z and raised to a nearly vertical state. The lifting force of the gripping part aO is the lid (1).
gives a large shear force applied in the direction perpendicular to the Furthermore, when the gripping part (IO) is pulled up, the starting end (11) of the fixed part of the tension opening piece (7) is lifted and torn by the lever action using the weakly rigid part a3 as a fulcrum, as shown in Figure 5, and the initial cleavage is facilitated. bring about

At this time, if there is a weakly rigid part (13), the resistance force that tries to lift the entire tension opening piece (7), which is thought to occur at the starting end (8) of the tension opening piece (7), is weak against the starting end (11). By using this resistance force as a shearing resistance force, initial cleavage is caused with less force. That is,
When lifting the gripping part (10 upwards, the starting end a of the fixed part
At 1), a lifting force is generated on M(1), and the lid (1)
A shearing force is generated between the force that tries to keep the surface flat. At this time, since the tension opening piece (7) is provided with the weakly rigid part (13), the tension opening piece (7> has its rigidity weakened by the weak rigidity part Q3, so that the lifting force is applied to the tension opening piece (7).
7) The lifting force is not transmitted to the entire part, and furthermore, the lifting force is bent around the weakly rigid part a3, giving a large shearing force, and easily causing initial cleavage.

In the above embodiment, as shown in the first diagram, in order to reduce the shearing force, the shape of the starting end CIt) of the fixed portion was made into a semicircular shape to reduce the width of the initial shearing.

During this initial cleavage operation, the tension opening piece (7) and M
If the adhesive layer (5) with (1) deteriorates over time, the starting end (one of the adhesive parts) of the tension opening piece (7) may peel off, but if the adhesive layer (5) is Since it is used, there is no fear of peeling, and as a result, the structure of the thin part α and the weakly rigid part (13) can function effectively.

Next, to explain the tearing process after the initial tearing of the above embodiment, the initial tearing occurs according to the above explanation, and when the grip part (IG) is pulled up, the lid (1) is opened at the guide edge starting from the X point. (
1! Opening edge (6) of ring-shaped member (3) along i+
The tear reaches the inner edge (171) starting from the y point, the outer tear progresses along the opening edge (6), and the tear on one side extends along the tensile opening piece (7). It is interrupted at approximately the center of the inner edge (+71). The reason why this inner tear is interrupted is that as the Ryogawa tear progresses, the lid (
This is because sagging occurs in the center of the ring-shaped member (3) and the concentration of tearing stress is dispersed.Therefore, the tearing stress is concentrated only in the part along the opening edge (6) of the ring-shaped member (3), and the outer tearing occurs. The only part connected to the end can be completely opened.

In this rapid tearing process of initial cleavage, if the adhesive layer (5) between the tensile aperture piece (υ and the lid (1) deteriorates over time, the stress for tearing will increase between the aperture edge (6) and the tensile aperture. It concentrates on the inner edge 0 of piece (7), and at that time, the inner edge (+7
), so that the tear penetrates under the tensile opening piece (υ) and, as a result, the tear along the inner edge (+71) may be interrupted before it progresses to the semicircumference. Although it is difficult to completely open the opening, since the resin composition is used for the adhesive layer (5), there is no such fear and the tearing along the inner edge (+7) can reliably proceed to the required semicircle. It can be done.

FIGS. 6 and 7 show another embodiment of the present invention, which is the same as the previous embodiment except that the shape of the tension opening piece (7) is different.

That is, the tension opening piece (7) is made of a band-shaped piece as in the previous embodiment, and continues from the annular part (7a) about 1 circumference from the starting end (8) having the gripping part aO, and further extends about 3/4 of the way to the outside thereof. An extended portion (7b) reaching an arc-shaped terminal portion (9) about
) has a spiral structure.

Both sections (7a) and (7b) are connected by a separable connecting piece ae with a slight gap. And the part (7
There is a terminal end (
9) and the opening edge (6) of the ring-shaped member (3).
We have set up a guide edge a@ towards .

Next, to explain the opening operation of this embodiment, pull up the grip part aG and use the thin part (121 and the weakly rigid part 13 to open the lid).
The process of causing initial cleavage in 1) is the same as in the previous example. After that, when the grip part (10) is further pulled up and the tension opening pieces (7) are successively lifted from the starting end (8) of the tension opening pieces (7>), the outer edge of the part (7a) (the part by 1!i1 The tear along the inner edge a8 of (7b) and the part (
The tear along the inner edge CIF) of 7a) progresses.

When the grip part (10) is further pulled up, the tear along the inner edge (+71) of the portion (1a) has progressed to approximately half the circumference, and as the lid (1) continues to break, the lid (1) becomes easy to bend. Thus only the tearing by the outer edge (Sl) of the part (7a) is sustained, which tearing is carried out by the guide edge (1@) at the opening edge (6) of the ring-shaped member (3).
heading to After that, the lid (1) between the part (7b) and the opening edge (6) is maintained in tension, and the inner edge 0e side of the part (7b) is torn, so the opening edge (6) is kept in tension. ), the tearing stress is concentrated only in the area along the opening edge (6), thus ensuring that the lid (1) is torn along the opening edge (6) and completely removed by this area (7b).

By forming the tension aperture piece (7) in a spiral shape in this way, the inner side that occurs in the tearing process after the above-mentioned initial cleavage in the case of a single tension aperture piece (7) as in the embodiment described above can be avoided. The stress concentrated on the edge 07) is reduced.

In the above embodiments, the tension aperture piece (7) has an adhesive layer (
Any material can be used as long as it can be bonded according to 5) and has a tensile strength that will not tear it off during a tearing operation.

However, in consideration of compatibility with the adhesive layer (5), it is preferable that the tension opening piece (7) be formed of the same resin as the adhesive layer (5).

In this case, in order to prevent the tension opening piece ('r) itself from deteriorating over time, it is preferable to form the tension opening piece (7) from the resin composition, and in this case, the adhesive layer (5) It has been found that the object of the present invention can be achieved even when the resin is made only of the above-mentioned resin without containing a phenolic antioxidant.

That is, in this case, the adhesive layer does not contain a phenolic antioxidant and is therefore susceptible to oxidative deterioration; however, since the adhesive layer is covered with the tensile aperture made of the resin composition, it is difficult to pass through the tensile aperture. Oxygen diffusion is prevented, and when the tensile aperture piece is rm-attached to the adhesive layer, the antioxidant contained in the tensile aperture piece diffuses into the adhesive layer, improving deterioration of the adhesive layer over time. demonstrate.

Furthermore, in this case, it goes without saying that it is optimal for the adhesive layer (5) to be the aforementioned resin composition containing a phenolic antioxidant.

(Example) As a carboxyl group-containing copolymer resin, ethylene-methacrylic acid copolymer resin Nuclell 407 (manufactured by DuPont Mikata Polychemical Co., Ltd., resin number 1) was used as an ionomer resin.Himilan 1652 (manufactured by DuPont Mikata Polychemical Co., Ltd.,
Using Resin No. 2), a phenolic antioxidant was melt-mixed with these resins to obtain resin compositions having the contents shown in Adhesive Nos. 1 to 15 in Table 1. This resin composition was made into a 30a thick film by the inflation method, and 60g of this was made into a film with a thickness of 30a.
An aluminum sheet material was obtained by heat-compression bonding to aluminum foil and further heat treatment at 200 to 240°C to laminate an adhesive layer.

This aluminum sheet material was fused to a crack ring-shaped member via an adhesive layer to obtain a lid material.

In addition, the same resin composition as the adhesive was used, a part of the grip part had a thickness of 0.6 mm, and a depth of 0.5 mm was formed near the grip part.
A V-shaped notch-shaped recess is provided, and the other part has a thickness of 1rn.
A tensile opening piece having the shape shown in Figure 6 of the IR was made by injection molding, and was heat-bonded to the upper surface of the adhesive layer of the lid material, except for the gripping part, to create a container lid.

Each test container was created by wrapping this around a tin cracked container body.

The adhesive layer and the tension opening piece of each test container were prepared using resin compositions corresponding to the adhesive numbers listed in Table 1 in combinations as shown in the structure of the container lid in Table 1.

Next, 100 cans of each test container were stored at 50°C for 60 days as a heating deterioration acceleration test condition, assuming that they were stored under high temperature conditions in the summer. evaluated. As a result, test numbers 3 to 9 and 13 to 18, which are examples of the present invention, had adhesive strengths that deviated by 1 degree over time and initial opening property (initial cleavage of the fixed part of the tension opening piece when the gripping part was pulled). The opening properties of the ring-shaped member in a given shape (the opening property of the ring-shaped member that cleaves into a predetermined shape defined by the opening edge) were both good as shown in Table 1.

In particular, test number 9.18 is an example in which the adhesive layer does not contain an antioxidant and only the tensile opening piece contains a predetermined amount of antioxidant, and as described above, it was good.

On the other hand, in the case of test number 1.11 where neither the adhesive layer nor the tension opening piece contains an antioxidant, the starting end of the fixed part of the tension opening piece is It peeled off, making initial cleavage difficult, and when the tension aperture piece was further pulled up, some of the tension aperture pieces peeled off.

In addition, in cases where both the adhesive layer and the tensile opening piece contain an antioxidant of less than the predetermined M as in test number 2.12, there is slight peeling at the starting end of the fixed part of the tensile opening piece during initial opening. Although the initial rupture was not difficult, a large pulling force was required, and when the ring-shaped member was torn along the opening edge after the initial rupture, the inner edge of the tension opening piece peeled off.

For this reason, when the tearing along the inner edge was interrupted before reaching the semi-circumference, and the entire circumference was opened by tearing along the opening edge of the ring-shaped member, torn pieces remained at the opening edge.

In test number 10.19, the adhesive layer did not contain antioxidant,
Only the tensile opening piece contained an antioxidant in a predetermined amount or less, and the same defects as in Test No. 2.12 occurred, and the occurrence frequency was high.

(Effects of the Invention) As is clear from the above description, according to the first aspect of the present invention, the adhesive layer for adhering the tension opening piece to the lid of the metal foil sheet is an olefin-α, β-unsaturated carboxylic acid co-adhesive layer. Since we used a resin composition containing 0.01 to 0.5% by weight of a phenolic antioxidant based on the synthetic resin or ionomer resin, the tensile opening is maintained even after long-term storage at high temperatures. When the ring-shaped member is torn open along the opening edge of the ring-shaped member, the outer guide edge provided on the piece does not cause peeling of the starting end of the adhesive part of the tension-opening piece or peeling of the inner edge of the tension-opening piece. This has the effect of providing an easy-to-open container with a lid that can be opened reliably without leaving any uncut parts.

Further, according to the second invention, the adhesive layer has olefin-α
, using a β-unsaturated carboxylic acid copolymer resin or an ionomer resin, and using a resin composition containing 0.01 to 0.5% by weight of a phenolic antioxidant based on the resin in the tensile opening piece; Since the tension opening piece and the adhesive layer are fused together, even if the ring-shaped member is stored under high temperature conditions for a long period of time and is eroded, the opening can be reliably cleaved along the opening edge of the ring-shaped member without leaving any residue. This has the effect of providing an easy-to-open container with a lid that can be opened easily.

[Brief explanation of drawings]

1 to 5 show an example of the implementation of the present invention. FIG. 1 is a plan view thereof, FIG. 2 is a sectional view taken along the line II-I of FIG. 1, and FIG. 4 and 5 are explanatory diagrams of the opening operation, and FIGS. 6 and 7 show other embodiments of the present invention, and FIG. 6 is a plan view thereof. 7 is a sectional view taken along the line ■-■ in FIG. 6. FIGS. 8 and 9 show a conventional example, and FIG. 8 is a plan view thereof, and FIG. There is a sectional view taken along the rXX line. (1) Lid (2) Container body (3) Ring-shaped member (5) Adhesive layer (6) Opening edge (7) Pull opening piece (8)...Starting end of the tension opening piece (9)...Terminal end of the tension opening piece aO...gripping part (l@...outer guide edge

Claims (1)

[Claims] 1. A lid made of a metal foil sheet is fixedly attached to the opening of the container body together with a ring-shaped member, and the upper surface of the lid has a gripping portion at one end, and the opening edge of the ring-shaped member In the easy-to-open container with a lid, the container has an outer guide edge facing toward the ring-shaped member, and has a band-shaped tensile opening piece along at least half the circumference of the opening edge of the ring-shaped member, which is fixed to the lid more firmly than the tear strength of the lid via an adhesive layer. The adhesive layer is a resin composition containing 0.01 to 0.5% by weight of a phenolic antioxidant based on an olefin-α,β unsaturated carboxylic acid copolymer resin or ionomer resin. An easy-to-open container with a lid. 2. A metal foil sheet lid is fixedly attached to the opening of the container body together with a ring-shaped member, and the upper surface of the lid has an outer guide edge that has a grip portion at one end and faces the opening edge of the ring-shaped member. In an easy-to-open container with a lid, in which a band-shaped tensile opening piece along at least half the circumference of the opening edge of a ring-shaped member is fixed to the container via an adhesive layer with a strength stronger than the tear strength of the lid, the adhesive layer and the tensile opening piece The opening piece is made of olefin-α,β unsaturated carboxylic acid copolymer resin or ionomer resin,
An easy-to-open type characterized in that the tension opening piece contains 0.01 to 0.5% by weight of a phenolic antioxidant based on the resin, and the tension opening piece and the adhesive layer are fused. Container with lid. 3. A patent claim characterized in that the tension opening piece is formed in an annular shape and has a starting end opposite to the terminal end thereof, and the guide edge facing the opening edge of the ring-shaped member is formed on the outside of the starting end. The easy-to-open lidded container according to item 1 or 2. 4. The tension opening piece is a band-like piece and is formed in a spiral shape with double inner and outer sides, and the inner end thereof is a starting end, and a gripping portion is provided at the starting end. 1
The easy-to-open container with a lid described in paragraph 2 or paragraph 2. 5. The easy-to-open lidded container according to claim 4, wherein a guide edge toward the opening edge of the ring-shaped member is formed in an intermediate portion adjacent to the terminal end of the pull opening piece. 6. The adhesive layer contains 0.01 phenolic antioxidant.
The easy-open lidded container according to claim 2, characterized in that the content ranges from 0.5% by weight to 0.5% by weight.